Not connected, rotten crossword layout (3-4)

I believe the answer is:

off-grid

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'not connected' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'rotten crossword layout' is the wordplay.
'rotten' becomes 'off' (rotten food is 'off').
'crossword layout' becomes 'grid' (as in a crossword grid).
'off'+'grid'='OFF-GRID'

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